Arrangement of rolling mills



March 9, 1965 K. E. JANSSON ARRANGEMENT OF ROLLING MILLS 3 Sheets-Sheet 1 Filed Nov. 27. 1961 March 9, 1965 K. E. JANSSON 3,172,312

ARRANGEMENT 0F ROLLING MILLS Filed Nov 27, 1961 3 Sheets-Sheet 2 March 9, 1965 K. E. JANSSON 7 3,172,312

ARRANGEMENT OF ROLLING MILLS Filed NOV. 27, 1961 3 Sheets-Sheet 3 United States Patent 3,172,312 ARRANGEMENT 6F ROLLING MILLS Karl Elis Jansson, Hagtors, Sweden, assignor to Morgarrlshammars Meir. Verkstads Aktiebolag, Morgardshammar, Sweden, a Swedish joint-stock company Filed Nov. 27, 1%1, Ser. 1 o. 155,076 Claims priority, application Sweden, Dec. 8, 1960, 11,899/60 Claims. (Cl. 72-234) This invention relates to an arrangement of rolling mills for rolling with controlled looping on looping tables, particularly for continuous hot rolling of wire and other small dimensions with the looping occurring between each roll pair.

Wire trains of the said type are previously known, the roll pairs being arranged perpendicularly to the main direction of the hot rolling material in the train. By controlling -the roll speeds, the loops formed between the roll pairs are given a certain size and shape. Said size and shape of the looping are to some extent subject to further control by return or guide pulleys arranged along the path of the hot rolling material. Threaded into such a pair of rolls, the hot rolling material runs straight between the roll pairs, but forms already after a few seconds a loop having on the looping table a shape which may he called three-curved, i.e. it runs first a short distance in the main direction of the hot rolling material through the wire train, curves then into one direction, for instance upwards, and thereafter via a point of inflection into another direction, preferably on the same plane, runs through a maximum point and a second inflection point, whereafter the loop curves and continues in the main direction of the hot rolling material through the train until it has passed the next pair of rolls where looping is repeated in like manner. When the last end portion of the hot rolling material runs through said three curves or is subjected to said three changes in direction, a whip cracker is formed which causes the hot rolling material to twist about the equipment fixed in its path, for example the entry guide, Where it is retained. In View of the high speed of the hot rolling material, usually between and 30 m./sec., such cracker formed at the last end portion will cause the last meters of the hot rolling material to be torn off. In modern continuous wire rolling mills the billets follow one another at such a speed, that there is no time for removing the retained scrap before the arrival of the next billet. As a result thereof, even the following billets are turned into scrap, as long as the mill is not stopped and the fault removed.

This disadvantage can be eliminated by subjecting the loop to adjusting, in such a manner, that between the roll pairs at the end of the hot rolling material the loop is stretched. The stretching is carried out by an operator who increases the speed of the preceding roll pair when he observes approach of the last portion of the hot material. However, in consideration of the high speed of the hot material and of the operators subjective judgment with respect to the speed to be added to the preceding roll pair. the said adjustment is quite fortuitous. As this decision by the operator, moreover, has to be taken within a few tenths of a second, one cannot expect it to be correct at all times. Consequently, sometimes cracker formation will occur or the hot material will be stretched somewhat too much. In the latter case, the hot material will undergo undesirable reduction in dimension.

It is the object of this invention to overcome the aforesaid drawbacks by preventing cracker formation and avoiding stretching of the material.

The conventional straight continuous rolling mill require a considerable construction length, in view of the space needed for the curves of the loop and the guide "ice rollers with associated equipment. The same problem is found in another conventional continuous rolling mill for high speed rolling where the hot material is subjected to curving by 180 degrees between the roll pairs. In this rolling mill the roll pairs are placed in staggered arrangement relative one another in order to facilitate their access for roll exchange and adjustment. Such arrangement results, of course, in greater space requirement.

It is a further object of the invention to reduce the construction length and space requirement.

The invention is substantially characterized in that the roll pairs are placed more or less angularly to follow the loop shape. The roll pairs are placed at such an angle to the substantially straight main direction of the hot rolling material, that the loop between two subsequent roll pairs forms one curve. Compared with the loop formed in conventional straight continuous rolling, the roll pairs according to this invention may be said to be placed in the inflection points of the loop obtained previously. Hereby the first and third curves of the threecurved loop formed in said rolling mills are eliminated.

The invention will be described in the following, reference being had to the accompanying drawings,

FIG. 1 of which shows in a schematic manner the arrangement of a rolling mill according to the invention, com rising alternating vertical and horizontal roll pairs,

FIG. 2 shows a rolling mill comprising only horizontal roll pairs,

FIG. 3 is an enlarged detail view of the arrangement in FIG. 1.

Referring to FIG. 1, two continuous trains of a wire rolling mill are indicated by 1 and 2. As both trains are analogous, only one of them will be referred to.

The wire arrives from a pair of conventional roll pairs 3 and 4 via a loop 5 at the first vertical pair 6 in train 1. Said pair is placed such, that the connecting line between theroll axes extends perpendicular to the loop path in the inflection point formed by the wave line 7 (11-2). The drive and gear means are placed beneath the roll pair. The hot material continues from roll pair 6 out to a looping table 8 which guides with its rear wall the hot material along a uniform curve into the following roll pair 9. Even this roll pair is placed angularly in rela-' tion to the main direction of the hot material. The roll axes of this pair are horizontal and arranged perpendicularly to the loop in the inflection point.

When the wire is rolled to desired dimension in said two roll pairs 6 and 9, it is taken out and coiled, as shown in schematic manner at 10, 10a and 10b, on coiling reels 11 and 13, respectively. If, however, the wire must be rolled down still more, it is threaded into the roll pairs 14, 15 via the loops 7b and 70, respectively. The wire may be taken out of t e roll pair 15 in like manner as de. scribed above, or it may continue via the roll pairs 16 and 17 to the coiling reel 11 or 12.

FIG. 2 shows in a schematic manner a wire rolling mill with continuous trains 21 and 22 in a wave line comprising only horizontal roll pairs. As the trains are identical in principle, it is only referred to one of them.

The wire 23 is threaded into the roll pair 24 and led out onto a looping table in like manner as in FIG. 1. From the roll pair 25 the hot material is led out to a looping table 25 of greater size and thereafter threaded into the roll pair 27. The greater size of looping table 26 is due to the greater space requirement of the drive and gear means 28 and 29. The arrangement of only horizontal roll pairs renders it thus necessary to provide for more space. In this case, space must be provided even for the twisting means between the roll pairs, which space can be provided according to this invention. The rolling, in general, is carried out in a manner analogous to FIG. 1.

35 includes a rear wall 36 in the form of an outer flange,

a bottom 37 and a front wall 33 in the form of an inner flange. The hot material is threaded from the looping table 35 into the horizontal roll pairs 39 with funnelshaped entry guide 40 and discharge guide 41 whereafter it continues to the next looping table 42. When being le out of the roll pair 32, the hot material follows the rear wall 36 of the looping table 35 and is threaded into the entry guide 40 with considerable force, which force is due to the better support imparted to the hot material by the new, simpler loop shape and the looping table designed in accordance therewith. By means of control means (not shown) the loop formed is then kept at a suitable distance from the wall.

For effecting and supporting the stable run of the hot material when being threaded in, the rear wall 36 of the looping table is shaped one-curved, the curve comprising substantially three circular arcs, namely a first arc with the radius R a second arc with the radius r, and a third are with the radius R R and R are considerably greater than r. In the example shown R =2 12 :6 2'.

When the last end portion of the hot material is to pass through the looping table, the end portion will follow the rear wall 36 and be given a stable run all the way to the entry guide 40 without having the possibiity of forming a cracker.

As appears from the above examples, the invention includes several advantages over the described prior state of art. The guide rollers, for example, needed for the previously known loops are now superfluous due to the invention which, in general, renders possible simplified rolling material by 180 degrees. As it was explain-ed invention both to straight arrangement of the roll pairs and to their staggering arrangement with curving the hot rolling materids by 180 degrees. As it was explained above, the threading process has gained in safety which also applies to the last mentioned case. After its curving by 180 degrees, the hot material must be advanced to the next pair in a tube, which advancing is in stable and may cause troubles.

As a further advantage of this invention may be mentioned that it renders possible rolling in two strands, in such a manner, for example, that the rear wall 36 is stepped. One loop is adjusted to zero position whereby the other loop will be drawn to the front wall 38.

What I claim is:

1. Arrangement of rolling mills for rolling with controlled looping on looping tables, characterized in that the looping tables comprise outer and inner stationary flanges rigidly connected with a bottom'part to hold the loop between said flanges, said flanges being arranged at a distance from each other which is sufliciently great for outer stationary flange which is curved in one direction only, when the last end is released from the foregoing stand and follows said flange to avoid double folding of the last end.

2. Arran ement of rolling mills as claimed in claim 1, characterized in that the angle between the planes through the axes of adjacent stands is greater than 0 and less than 180.

3. Arrangement of rolling mills as defined in claim 1 wherein each said looping table is located intermediate adjacent roll stands one of which is comprised of a pair of vertical rolls and the other of which is comprised of a pair or" horizontal rolls, and the rolled material undergoes substantialy a 90 change in direction on said looping table in passing between said adjacent roll stands, the outer flange of said looping table being comprised of a central and two end sections all of which are curved to establish a continuous curved wall of different radii of curvature, the radius of curvature of said curved end sections being considerably greater than the radius of curvature of said curved central section.

4. Arrangement of rolling mills as defined in claim 3 wherein the radius of curvature of the end section of said outer flange at the material leaving side from said looping table is about twice the radius of curvature of the other end section at the material entrance side of said looping table.

5. Arrangement of rolling mills as defined in claim 3 wherein the radius of curvature of the end section of said outer flange at the material leaving side from said looping table is about twice the radius of curvature of the other end section at the -rnaterial entrance side to said looping table and about six times greater than the radius of curvature of said central section of said outer flange.

References Cited by the Examiner UNITED STATES PATENTS 1,752,841 4/30 George -51 3,122,949 3/ 64 Brandenburg et al. 8035 FOREIGN PATENTS 1,125,662 7/56 'France.

934,462 10/55 Germany' 10,452 7/98 Great Britain. 16,260 7/07 Great Britain.

WILLIAM J. STEPHENSON, Primary Examiner, LEON PEAR, Examiner. 

1. ARRANGEMENT OF ROLLING MILLS FOR ROLLING WITH CONTROLLED LOOPING ON LOOPING TABLES, CHARACTERIZED IN THAT THE LOOPING TABLES COMPRISE OUTER AND INNER STATIONARY FLANGES RIGIDLY CONNECTED WITH A BOTTOM PART TO HOLD THE LOOP BETWEEN SAID FLANGES, SAID FLANGES BEING ARRANGED AT A DISTANCE FROM EACH OTHER WHICH IS SUFFICIENTLY GREAT FOR CONTROLLING THE POSITION OF THE LOOP BY MEANS OF THE SPEED OF THE STANDS, THAT THE OUTER STATIONARY LOOPING TABLE FLANGE IS CURVED IN ONE DIRECTION ONLY TO ENABLE ROLLING WITH UNLIMITEDLY HIGH SPEEDS, THAT ADJACENT STANDS ARE PLACED AT SUCH AN ANGLE IN RELATION TO EACH OTHER AND IN RELATION TO THE OUTER LOOPING TABLE FLANGE THAT THE LOOP 